Steam DeSuperheater is used to spray water into steam, so that it gets mixed, resulting in reduction in the temperature at the outlet.
DeSuperheater can be classified into two:
A. Non-Integral type DeSuperheater: DeSuperheater nozzle and water valve are separate units.
B. Integral type DeSuperheater: DeSuperheater is in-built with actuator, so that there is no need of separate spray water valve.
Split PRDS: separate PRV (Pressure Reducing Valve) and DeSuperheater
Combined PRDS: Both PRV and DeSuperheater in a compact single unit
Nozzles are also classified into:
A. Venturi type: where nozzle orifice is fixed irrespective of flow variation.
B. Variable orifice: where orifice area opening will vary according to the flow and pressure variations.